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The NASA Mars Science Laboratory (MSL) rover, Curiosity, has safely landed near a 35-km-long dark dune field in Gale Crater on Mars. This dune field crosses the landing site from the northeast to the southwest and lies along Curiosity's traverse to Aeolis Mons. Here we present the first evidence of recent aeolian activity in the form of ripple and dune migration, and further estimate wind directions within the dune field through analysis of ripple and dune morphologies and the Mars Regional Atmospheric Modeling System (MRAMS). We measured a minimum ripple migration rate of 0.66 m per Earth year, and dune migration rate of 0.4 m per Earth year, in the southwest portion of the field. A strongly bidirectional ripple crestline orientation, nearly orthogonal dune slipfaces, and linear seif or oblique dunes indicate a bidirectional wind regime with winds mainly coming from the ENE and from the northwest; however, MRAMS results indicate primary winds from the ENE. Our constraints on the wind regime provide the unique opportunity to use ground measurements from MSL to test the accuracy of winds predicted from orbital data. [ABSTRACT FROM AUTHOR]

Eolian landforms in Estancia basin, central New Mexico, record two episodes of extreme drought and low groundwater levels during the middle Holocene (7000-5400 [sup 14]C yr B.P.), followed by a rise in the water table through the late Holocene. Blowouts and associated lunettes formed when water levels fell below the desiccated floor of pluvial Lake Estancia, allowing widespread deflation. Elevation of the water table in the basin is regulated by a balance between evaporation from playas that occupy the blowouts and recharge of aquifers in the adjacent Manzano Mountains. Isotopic analyses of modern precipitation and groundwater reveal that recharge originates primarily as winter moisture, which is amplified during El Niños and diminished during La Ni˜as. Thus, changes in the elevation of a reconstructed Holocene water table may reflect systematic changes in El Niño-Southern Oscillation (ENSO) circulation. [ABSTRACT FROM AUTHOR]

At Capitol Reef National Park, Utah, 5-m-high stromatolites are present locally on interdune carbonate lenses in the Early Jurassic Navajo Sandstone. The stromatolites display both finely laminated and fenestral internal fabrics, and grew along south-facing interdune margins. These stromatolites formed during a high-water-table episode engendered by a dune-dammed paleodrainage in a stabilized Navajo erg. These stromatolites, and the thick interdune section associated with them, suggest a hiatus in erg accumulation and the presence of a super bounding surface. [ABSTRACT FROM AUTHOR]

Examines the Jurassic thick eolian deposits, flexure of the United States (US) continental interior and timing of the shortening events in the US Cordillera. Tectonic loads and stratigraphic history; Burial curves history; Three-dimensional flexural modeling.

Documents the provenance of Quarternary sands in the Big Lost trough by petrographic analysis and detrital-zircon U/Pb geochronology to determine the distribution of the fluvial systems of the Big Lost River and Little Lost River in Idaho. Composition of modern fluvial and eolian sands; Alternating clay-rich lacustrine deposits and sand-rich deposits.

Analyzes the sediment components in Elk Lake, Minnesota to determine the rates, timing and cyclicity of Holocene eolian activity. Allochtonous components of the sediments; Composition of the eolian dust; Interpretation of data in terms of regional climate change.